1. Field of the Invention
The present invention relates to an insert injection-molded case that is typically used for electronic devices. More particularly, the present invention is related to an insert injection-molded case which includes an injection-molded case body formed during insert injection-molding.
2. Description of the Related Art
In general, an injection molding machine is adapted to injection-mold a resin using a mold to form an injection-molded product such as a housing or case for a portable communication device, a cosmetic case, and a monitor case. In particular, an insert injection-molded product is formed by inserting a metal plate into a mold and injection-molding a resin to integrally form with the metal plate within the mold.
Conventionally, such an injection-molded product is deformed by heat generated during a cooling operation after insert injection-molding.
In order to prevent the deformation problem, a glass fiber (hereinafter, referred to as “GF”) resin is contained within an injection-molded product.
However, when a GF resin is contained in a conventionally injection-molded product, glass components of the GF resin disadvantageously protrude from the appearance of the injection-molded product. Thus, as thickness of an injection-molded product increases, the overall slimness of the product is adversely affected. Also, as an outer surface of the injection-molded product is irregular, there is difficulty in depositing a metallic feeling layer or achieve a metallic feeling (for example, a glossy metallic feeling) desired by a user during deposition.
Further, since glass components of the GF resin often protrude from an appearance of the injection-molded product, a defect rate of the product under manufacture is higher than desired and an expensive GF resin is necessary, thus increasing the manufacturing costs of the injection-molded product.
In addition, due to the shifting of a metal plate during insert injection-molding, a failure rate of an injection-molded product disadvantageously increases.
Therefore, there is a need in the art to form an injection-molded product that does not utilize conventional GF resin in order to avoid the drawbacks of such conventional construction.